Tire manufacturing method

ABSTRACT

A tire manufacturing method includes the steps of, when a green tire is molded, moving a toroidally expandable toroidal molding drum through a distance between a plurality of working stations at a specified tact time, disposing a carcass band and both bead cores on the drum in any working station and locking the bead cores, increasing the diameter of the molding drum, toroidally extending the carcass band between both bead cores, and rolling up the side portion of the carcass band around the bead cores in the outer radial direction, assembling tire component members with the bead cores locked to the toroidal molding drum and molding the green tire, and reducing the diameter of the molding drum, unlocking the bead cores, and removing the green tire from the molding drum, whereby the tires of a plurality of sizes can be sequentially molded, a conventional tire structure must not be largely changed, and an energy and time can be prevented from being wastefully consumed.

TECHNICAL FIELD

The present invention relates to a tire manufacturing method which cansupport high productivity of a plurality of sizes of product tireschosen from a group of sizes specified in advance, even in the case ofmanufacturing of different sizes of tires in tandem and particularly toa method capable of manufacture without largely changing a conventionaltire structure.

BACKGROUND ART

A tire manufacturing system, particularly a molding system for molding agreen tire has been increasingly sophisticated and complicated recentlyto respond to a request for upgrading of a tire quality and improvementof productivity, and improvement of tire manufacturing capacity whilerestraining an occupied space and a cost of a molding system is indemand. Therefore, instead of provision of a plurality of conventionaltire molding machines for assembling various tire component members at asingle place, a plurality of working stations where tire componentmembers are assembled according to them are provided and a moldingsystem for conveying a tire being molded between these stations at apredetermined tact time is used. But with this molding system, it isdifficult to switch and assemble tire component members corresponding toplural sizes at each station within a predetermined tact time, andsmall-lot production can not be supported since tires in mixed differentsizes can not be molded continuously, which extremely limits itspractical application.

In order to solve this problem, as disclosed in the InternationalPublication WO 01/39963, a system capable of continuous molding of agroup of tires in mixed plural sizes is proposed, and this moldingsystem comprises the steps of assembling each tire component members ona rigid core with the cross section in the toroidal shape, forming agreen tire on the rigid core, vulcanizing the tire while being mountedon the rigid core and taking the cured tire out of the rigid core at thelast stage.

However, this molding system has the following problems. First,structural change from the conventional tire is inevitable since membersare assembled on the rigid core, and since the conventional structure inwhich one or more layers of carcass ply is rolled up around each beadcore outward in the tire radial direction can not be used, a new tirestructure so as to fix the carcass onto the bead core should beemployed, but reliability of this new tire structure has not been fullyestablished yet.

The second problem is, a rigid core used both in molding a green tireand vulcanizing the molded green tire should be held at a roomtemperature in the molding process but the temperature should be raisedin the vulcanizing process. Therefore, energy and time for heating andcooling the rigid core is wasted.

The present invention has been made in view of the above problems andhas an object to provide a tire manufacturing method in which tires inmixed plural sizes can be molded continuously by moving the tire beingmolded between working stations and moreover, the conventional tirestructure does not have to be largely changed or energy and time can beprevented from being wastefully consumed.

DISCLOSURE OF THE INVENTION

The present invention was made to achieve the above object and its gist,construction and action will be described below.

(1) The present invention is a tire manufacturing method having aprocess for, in manufacturing product tires in plural sizes chosen froma group of sizes specified in advance, moving a tire being moldedsequentially between stations of a molding system having a plurality ofworking stations, sequentially assembling tire component membersspecified in advance corresponding to each working station and molding agreen tire at a predetermined tact time, and a process for vulcanizingthe molded green tire, to be performed at one or more working stationsof said molding system:

molding a green tire based on the molding sequence specified in advance,including combination of green tires in different sizes in tandem chosenas necessary from said group of sizes,

disposing a carcass band and both bead cores on a toroidal molding drumwhose diameter can be expanded/reduced in the toroidal shape and lockingthe bead cores, expanding the diameter of the molding drum, toroidallyextending the carcass band between both bead cores, rolling up the sideportion of the carcass band around the bead cores outward in the radialdirection, assembling tire component members with the bead cores lockedto the toroidal molding drum and molding the green tire, reducing thediameter of the molding drum, unlocking the bead cores, and removing thegreen tire from the molding drum.

According to the tire manufacturing method of the present invention,since the carcass band is rolled up around the bead cores on thetoroidal molding drum whose diameter can be expanded/reduced in thetoroidal shape, a tire structure with conventional high reliability canbe formed, and also, since the green tire is removed from the toroidalmolding drum at the end of the molding process, it is only necessary toheat the green tire in the subsequent vulcanizing process, wherebywasteful energy must not be spent. And since the green tire is moldedbased on the molding sequence specified in advance, includingcombination of green tires in different sizes in tandem chosen asnecessary from said group of sizes, tires in mixed plural sizes can becontinuously molded.

Moreover, in this tire manufacturing method, a green tire is molded byrolling up the side portion of the carcass band around the bead coresoutward in the radial direction and then, assembling the tire componentmembers such as a belt member, a tread member, etc. with the bead coreslocked to the toroidal molding drum and molding the green tire. So, incomparison with the method of assembling these tire component members byholding a central portion in the width direction of the carcass bandinflated in the toroidal shape instead of locking the bead cores to thetoroidal molding drum, positioning of these tire component members to beassembled and the molding drum can be made highly accurate and by this,the accuracy of relative positions of the bead core and these tirecomponent members can be improved, and a tire with high accuracy andexcellent uniformity performance can be formed.

(2) The present invention further provides a tire manufacturing methodaccording to item (1), wherein, in forming said carcass band, thismember is assembled onto a cylindrical molding drum to form a carcassband at working stations corresponding to an inner liner member and acarcass member, respectively, and then, the carcass band is removed fromthe cylindrical molding drum,

in molding said green tire, after said process for rolling up the sideportion of the carcass member on the toroidal molding drum, the beltmember, the tread member and a sidewall member are assembled at therespective corresponding working stations.

According to this aspect of the tire manufacturing method, since thebelt member, the tread member and the sidewall member are assembled onthe molding drum whose diameter has been expanded toroidally,deformation of these members after assembling can be minimized, andsince the inner liner member and the carcass member whose influence onthe quality can be ignored even if they are toroidally deformed afterassembling are assembled on the cylindrical molding drum, efficientassembling can be realized, and the simple drum shape as a cylinderenables support of many sizes with a single type of drum.

(3) The present invention further provides a tire manufacturing methodaccording to item (1) or (2), wherein at least one tire component memberto be assembled at said working station is comprised of one type ofmember element specified in advance and common to said group of sizes,and a green tire is molded by assembling the member element by an amountspecified in advance for each tire component member for all the sizes insaid group.

According to this aspect of the tire manufacturing method, since the atleast one tire component is comprised of one type of member elementcommon to said group of sizes, an apparatus for manufacturing this tirecomponent member and an apparatus for assembling thereof can beconstituted extremely simply, and since many sizes can be supported byassembling the member element by an amount specified in advance, sizecan be switched in an extremely short time and tires in mixed pluralsizes can be manufactured efficiently.

(4) The present invention further provides a tire manufacturing methodaccording to item (3), wherein at least one of said tire componentmembers has a rubber ribbon made of a predetermined materialcontinuously extruded through a die with a predetermined sectional shapeas said member element, this rubber ribbon is wound on a cylindrical ora toroidal molding drum in the spiral shape and this is laminated in thepredetermined sectional shape, and this tire component member isassembled.

According to this aspect of the tire manufacturing method, since onetype of continuous rubber ribbon is wound in the spiral shape andlaminated, a tire component member in the different sectional shape canbe assembled according to the tire size only by changing the way tolaminate the rubber ribbon, and the size can be switched in a shorttime.

(5) The present invention further provides a tire manufacturing methodaccording to item (3) or (4), wherein at least one of said tirecomponent members has a continuous sheet with a predetermined width madeof a predetermined material as said member element, this continuoussheet is cut into the length specified in advance per size, narrowpieces in the number predetermined for each size are joined to eachother so that the cut-off faces of the cut-off narrow pieces are alignedin the circumferential direction on the molding drum, and this tirecomponent member is assembled.

According to this aspect of the tire manufacturing method, thecontinuous sheet is cut into the length specified in advance per sizeand narrow pieces are disposed on the molding drum so as to assemblethis tire component member. So, by choosing the width of the continuoussheet so that members for a single tire can be formed if the integralnumber of narrow pieces are aligned for any tire size, tire componentmembers with different width or circumferential length depending on thetire size can be assembled only by changing the cutting length or thenumber of pieces, and size switching can be performed in a short time.

(6) The present invention further provides a tire manufacturing methodaccording to item (3), wherein a tread member and a sidewall member areincluded in tire component members having the rubber ribbon in (4) assaid member element, and an inner liner member, a carcass member and abelt member are included in tire component members having the continuoussheet with a predetermined width in (5) as said member element.

According to this aspect of the tire manufacturing method, sinceessential members are assembled in the above-mentioned method, switchingof many sizes can be performed in a short time.

(7) The present invention further provides a tire manufacturing methodaccording to any one of items (3) to (6), wherein, as for at least onetire component member, said member element is directly assembled onto acylindrical or a toroidal molding drum.

According to this aspect of the tire manufacturing method, since saidmember element is assembled directly onto the molding drum without astock, a space for storing intermediate materials of this member can besaved, and also, size change immediately before can be supported,whereby more flexible manufacturing is realized.

(8) The present invention further provides a tire manufacturing methodaccording to any one of items (3) to (6), wherein, as for at least onetire component member, said member element for a single tire is combinedand then, the combined member element is assembled on a cylindrical or atoroidal molding drum.

According to this aspect of the tire manufacturing method, by formingand preparing said member element for a single tire in advance, a timefor assembling onto the molding drum can be reduced, and if theassembling time is a bottleneck in reducing a tact time, when this isdirectly assembled to the molding drum, the time can be reduced.

(9) The present invention further provides a tire manufacturing methodaccording to any one of items (1) to (8), wherein among idle time ateach of the working stations corresponding to each tact determined basedon said molding sequence specified in advance, a tact time is changedfor the respective tact so that the shortest idle time becomes shorter.

According to this aspect of the tire manufacturing method, since thetact time can be changed for the respective tact depending on thecombination of tire sizes during molding as above so that the timebecomes the shortest, the average number of molded tires per time can beincreased.

(10) The present invention further provides a tire manufacturing methodaccording to any one of items (1) to (9), wherein an estimate equationis prepared in advance to estimate a primary harmonic component ofradial run-out in a green tire caused by a relative displacement orangular displacement between the center of axis of the carcass band andthe center of axis of the bead core in setting the bead core on theouter circumference of the carcass band,

radial run-out of the green tire is measured for one cycle and aninverted waveform in which the primary harmonic component is inverted isobtained,

in molding a tire of the same size in said molding system thereafter, arelative displacement or an angular displacement between the center ofaxis of the carcass member and the center of axis of the bead corecausing this inverted waveform is obtained by back calculation of saidestimate equation, and the position or the angle of at least either oneof the bead core axis centers is changed by the magnitude of thedisplacement acquired from this estimate equation in the direction ofthe displacement acquired from this estimate equation so as to set thebead core on the carcass band.

It is known that the circumferential phase and the amount of relativedisplacement or angular displacement between the center of axis of thecarcass band and the center of axis of the bead core has a strongcorrelation with the amplitude of the primary harmonic component of theradial run-out of the green tire, and it is also known that there is astrong correlation between the radial run-out of the green tire and RFVof the product tire.

According to this aspect of the tire manufacturing method, the moldingsystem can be constructed so that the setting position or angle of thebead core can be controlled, the radial run-out of the green tire ismeasured for one cycle, the measurement result is used and the settingposition or angle of the bead core is controlled with respect to thegreen tire to be molded after that so as to reduce the radial run-out ofthe green tire, whereby RFV of the product tire can be lowered and theuniformity can be improved.

(11) The present invention further provides a tire manufacturing methodaccording to any one of items (1) to (10), wherein vulcanization of themolded green tires is started sequentially at said predetermined tacttime and vulcanization of these tires is finished at said predeterminedtact time.

According to this aspect of the tire manufacturing method, sincevulcanization of the tire is started and finished in synchronizationwith molding of the green tire, an intermediate stock between the tiremolding system and the tire vulcanization system and the intermediatestock within the tire vulcanization system can be minimized.

(12) The present invention further provides a tire manufacturing methodaccording to any one of items (1) to (11), wherein inspection of thevulcanized tire is started at said predetermined tact time.

According to this aspect of the tire manufacturing method, since theinspection of tire is conducted in synchronization with tirevulcanization, an intermediate stock between the tire vulcanizationsystem and the tire inspection system can be saved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an arrangement plan showing a tire manufacturing systemaccording to a preferred embodiment of the present invention.

FIG. 2 is an arrangement plan showing a tire molding system.

FIG. 3 is a sectional view showing a tire being molded.

FIG. 4 is a sectional view showing a tire being molded.

FIG. 5 is a sectional view showing a tire being molded.

FIG. 6 is a sectional view showing a tire being molded.

FIG. 7 is a sectional view showing a tire being molded.

FIG. 8 is a sectional view showing a tire being molded.

FIG. 9 is an explanatory view showing a ribbon laminating method.

FIG. 10 is an explanatory view showing a predetermined-widthnarrow-piece method.

FIG. 11 is an arrangement plan of a tire vulcanization system.

FIG. 12 is a side view showing a mobile vulcanization unit.

FIG. 13 is a front view showing a vulcanization station and a moldopening/closing station.

FIG. 14 is a plan view showing a vulcanization station and a moldopening/closing station.

FIG. 15 is an arrangement plan showing a tire manufacturing system ofanother preferred embodiment.

FIG. 16 is an arrangement plan showing another tire manufacturingsystem.

FIG. 17 is an arrangement plan showing another tire manufacturingsystem.

FIG. 18 is an arrangement plan showing another tire manufacturingsystem.

BEST MODE FOR CARRYING-OUT OF THE INVENTION

A preferred embodiment of the present invention will be described belowbased on FIGS. 1 to 18.

FIG. 1 is an arrangement plan of a tire manufacturing system 1 used fora tire manufacturing system of this preferred embodiment, and the tiremanufacturing system 1 is provided with a tire molding system 2, a tirevulcanization system 3 and a tire inspection system 6, and in the first,the tire molding system 2 and a method for molding a green tire will bedescribed based on the arrangement plan of the tire molding system 2shown in FIG. 2.

The tire molding system 2 is comprised of a first molding unit 4 and asecond molding unit 5 arranged adjacent to each other, and the firstmolding unit 4 is provided with three working stations C1, C2 and C3, afirst molding carriage 12 supporting a cylindrical molding drum 11 inthe cantilever manner and rotating it around the spindle, a transfercarriage 14, and a straight track 13 for guiding movement of the firstmolding carriage 12 among the working stations C1, C2 and C3.

The second molding unit 5 is provided with 9 working stations F1 to F9,a second molding carriage 22 for supporting a toroidal molding drum 21in the cantilever manner and rotating it around the spindle, an endlesstrack 23 for guiding movement of the second molding carriage 22 amongthe working stations F1 to F9, a green tire transfer carriage 24, and agreen tire conveyer 25 for conveying the green tire to the vulcanizationsystem.

The first molding carriage 12 on which the cylindrical molding drum 11is loaded repeats movement from the working station C1 to C2, C2 to C3and C3 to C1 in this order at a predetermined tact time, while thetransfer carriage 14 repeats reciprocation between the working stationC3 and F1. Also, the second molding carriage 22 on which the toroidalmolding drum 21 is loaded repeats clockwise movement to each workingstation such as from the working station F1 to F2 at a predeterminedtact time. In the tire molding system 2 of the preferred embodimentshown in the FIG. , one unit of the first molding carriage 12 and eightunits of the second molding carriages are provided, each of thecarriages 12 and 22 being moved by a driving device, not shown, betweenthe working stations, and after being stopped at each of the workingstations, they are positioned by a positioning device provided at eachof the working stations with high accuracy.

FIGS. 3 to 8 are radial sectional views, showing a tire being moldedusing this molding system 2 per. step, including a central axis of thedrum. First, at the working station C1, using an inner liner memberassembling device 15 and a canvas chafer member assembling device 16,each of an inner liner member IL and a canvas chafer member CCH to bearranged on its outer circumference in the radial direction areassembled onto the cylindrical molding drum 11, as shown in FIG. 3(a),and then, the cylindrical molding drum 11 is moved to the workingstation C2, where, using a squeegee member assembling device 17 and acarcass member assembling device 18, as shown in FIG. 3(b),one or twolayers of squeegee member SQ and one or two layers of carcass member Pare assembled outside the inner liner member IL and the canvas chafermember CCH in the radial direction so as to form a carcass band CB.

FIG. 3(b) shows an example in which the squeegee member SQ and thecarcass member P are provided in one layer, respectively, but when theyare provided in two layers, they are assembled in the order from theinner-layer side squeegee member SQ, the inner-layer side carcass memberP, the outer-layer side squeegee member SQ and the outer-layer sidecarcass member P. The cylindrical molding drum 11 is constructed andarranged capable of expanding/reducing the diameter of each of aplurality of segments formed by being divided in the circumferentialdirection, and a tire component member is arranged on the circumferenceof the cylindrical molding drum 11 in the diameter expanded state.

In the meantime, at the working station C3, a pair of preset beads PB ineach of which a bead filler is preset on the bead core is set on thetransfer carriage 14. And as shown in FIG. 3(c), the carcass band CB isarranged inside the pair of preset beads PB having been set in theradial direction. That is, the transfer carriage 14 is provided with abead holding ring 14 a capable of diameter expansion/reduction forholding each of the preset beads PB from their side faces and a bandholding ring 14 b capable of diameter expansion/reduction for holdingthe carcass band CB from outside in the radial direction, and at theworking station C3, the preset bead PB is taken out of a bead stock 19 busing a bead handling robot 19 a, and after this is transferred to thebead holding ring 14 a and held by the bead holding ring 14 a, thetransfer carriage 14 is made to stand by in this state, and then, thecylindrical molding drum 11 with the carcass band CB assembled isinserted inside the pair of present beads PB having been set in theradial direction up to a predetermined position in the axial direction.After the diameter of the band holding ring 14 b is reduced so that thecarcass band CB is held from outside in the radial direction, thediameter of cylindrical molding drum 11 is reduced and the carcass bandCB is transferred from the cylindrical molding drum 11 to the transfercarriage 14, as shown in FIG. 3(c).

In the above, the preset bead PB on which the bead filler and the beadcore are preset in advance is set on the transfer carriage 14, butinstead, it may be so constituted that at the working station C3, onlythe bead core is set on the transfer carriage 14 and the bead filler isassembled at the working station F2, which will be described in detaillater, or at another exclusive working station which is to be added.

Next, the transfer carriage 14 holding the preset beads PB and thecarcass band CB is moved to the working station F1 where the toroidalmolding drum 21 is on standby, as shown in FIG. 4(a), and both thepreset beads PB and the carcass band CB are transferred onto thetoroidal molding drum 21, as shown in FIG. 4(b).

This step is described in detail as follows. The toroidal molding drum21 is provided with a right and left pair of core bodies 21 a comprisedof a plurality of rigid segments adjacent to each other in thecircumferential direction and capable of expansion/contractiondisplacement, a right and left pair of bead lock portions 21 b similarlyadjacent to each other in the circumferential direction and comprised ofrigid segments capable of expansion/contraction displacement, carcassrolling-up rods 21 c provided at right and left ends in the axialdirection and arranged in plural in the circumferential direction, and acenter bladder 21 d arranged outside of the core body 21 a in the radialdirection and made of a flexible material inflating toroidally by supplyof internal pressure, and it is so constituted that the core body 21 a,the bead lock portion 21 b and the carcass rolling-up rod 21 c on thesame right or left side is provided on a right or left slider so thatthese 21 a, 21 b and 21 c can be integrally displaced in and outside inthe axial direction. And with the present bead PB being held by the beadholding ring 14 a and the carcass band CB by the band holding ring 14 b,the transfer carriage 14 is moved to the station F1 and they arearranged outside the toroidal molding drum 21 standing by in the statewhere the bead lock portion 21 b is brought close to the shaft end toreduce the diameter, the diameter of the bead lock portion 21 b isexpanded and the preset bead PB is fixed onto the toroidal molding drum21. And then, the diameters of the bead holding ring 14 a and the bandholding ring 14 b are expanded to release their constraint, and thetransfer carriage 14 is returned to the working station C3. In this way,the present beads PB and the carcass band CB can be transferred onto thetoroidal molding drum 21.

Next, the toroidal molding drum 21 is moved to the working station F2,where, as shown in FIG. 5(a), the center part of the carcass band CB inthe width direction is inflated in the toroidal shape and then, the sideof the carcass member P is rolled up outside in the radial direction.This process is carried out as follows. While an internal pressure isapplied to the center bladder 21 d to inflate and deform it, the sliderson both sides with the bead lock portions 21 b and so on mounted aremoved toward the center in the axial direction, and at the same time,the diameters of the right and left core bodies 21 a are also expandedso that the center part in the width direction of the carcass band CB isinflated and deformed in the toroidal shape, and in the middle of thisinflation/deformation, a claw 26 a provided at an external drivingdevice 26 and engaged with the rear end of the carcass rolling-up rod 21c is moved toward the center in the axial direction so as to advance anddisplace the carcass rolling-up rod 21 c in the same direction so thatthe tip end of the rolling-up rod 21 c is displaced by a link mechanism,not shown, along the side face of the core body 21 a whose diameter waspartially expanded and the side portion of the carcass member P can berolled up around the preset beads PB. After that, the diameter of thecore body 21 a is expanded to the maximum to fulfill the function tosupport the tire component members to be subsequently assembled andhence, their assembling external force from inside in the radialdirection, by which assembling accuracy of each member can be improved.

Or, at this working station F2, for example, waveform of the radialrun-out of the carcass band inflated and deformed in the toroidal shapecan be measured for one cycle. Here, the waveform of the radial run-outof the carcass band CB inflated and deformed in the toroidal shaperefers to the waveform of change in the circumferential direction of theradius distance from the center of axis of rotation of the molding drumat the center in the axial direction of the inflated carcass band. Andthe phase f of its primary harmonic component and the amplitude Y is fedback to the process at the working stations C3 and F1 mentioned above.That is, one of both bead holding rings 14 a of the transfer carriage 14standing by at the working station C3 is constituted so that itsorientation of the center of axis is controlled without stages in apredetermined direction, within a horizontal plane, for example, and asa first operation, at the working station C3, after the preset beads PBare set on the bead holding ring 14 a, the center of axis of the beadholding ring 14 a is inclined by an angle a determined uniquely from theamplitude Y measured at the working station F2. Here, the angle a meansan angle required to cancel the amplitude Y.

Next, as the second operation, at the working station F1, the moldingdrum 21 set at the standard position in the circumferential direction isrotated by the phase f measured at the working station F2 prior to thebead lock. By these first and second operations, information of theprimary harmonic component of the radial run-out of the carcass band CBinflated and deformed in the toroidal shape is fed back to the tire tobe molded after measurement of the radial run-out waveform so that theabove radial run-out can be improved by canceling the primary harmoniccomponent of the radial run-out, whereby the RVF level of the producttire having correlation with the radial run-out can be improved.

In the above, the bladder 21 d is provided at the molding drum 21, andthe carcass band CB is inflated and deformed by supplying an internalpressure into this bladder 21 d, but the carcass band CB can be alsoinflated and deformed without using the bladder 21 d. In that case, thisis accomplished by placing a rubber seal for sealing the internalpressure on the outer circumferential face of the bead lock portion 21 band supplying the internal pressure supplied into a space enclosed bythe bead lock portion 21 b and the carcass band CB.

After that, the molding drum 21 is sequentially moved to the workingstations F3 to F8, and the following operations are to be performed. Atthe working station F3, using an inner-layer belt member assemblingdevice 27, an inner-layer belt member 1B is assembled with the core body21 a with the expanded diameter as the base, as shown in FIG. 5(b), andthen, at the working station F4, using an outer-layer belt memberassembling device 28, an outer-layer belt member 2B is assembled, asshown in FIG. 6(a).

At the working station F5, using a spiral layer member assembling device29 and a tread under-cushion member assembling device 30, a spiral layermember SL is assembled, as shown in FIG. 6(b), and outside the spirallayer member SL in the radial direction, a tread under-cushion memberTUC is assembled.

At the working station F6, using a base tread member assembling device31 and an antenna member assembling member 32, a base tread member BASEarranged on both sides of the tire in the axial direction and a highlyconductive antenna member ATN arranged adjacent to these members at thecenter part of the tire in the axial direction are assembled, as shownin FIG. 7(a), and then, at the working station F7, using a cap treadmember assembling device 33 and an antenna member assembling device 32,a cap tread member CAP arranged on both sides of the tire in the axialdirection and a highly conductive antenna member ATN arranged adjacentto these members at the center part of the tire in the axial directionare assembled, as shown in FIG. 7(b).

At the working station F8, on both side faces of the tire being molded,a sidewall member SW is assembled using a sidewall member assemblingdevice 34, as shown in FIG. 8(a), and then, inside it in the radialdirection, a rubber chafer member GCH is assembled using a rubber chafermember assembling device 35.

As mentioned above, since the molding drum 21 is provided with the beadlock portion 21 b, the shaping bladder 21 d and the core body 21 acapable of expansion/contraction displacement, operations from extensionof the carcass band CB into the toroidal shape to assembling of the beltmember and the tread member can be accomplished with the tire beingmolded bead-locked on this drum 21, and tire qualities such asuniformity can be improved as compared with the conventional moldingmethod in which the bead lock of the tire being molded should bereleased and transferred between the working stations between theseoperations.

At the last working station F9, after the operation such as applicationof a barcode, the finished green tire GT is removed from the moldingdrum 21 and transferred to the green tire transfer carriage 24. Thegreen tire transfer carriage 24 is provided with a holding ring 24 acapable of expansion and contraction for holding the green tire GT fromoutside in the radial direction, and in transferring the green tire GTfrom the molding drum 21 to the transfer carriage 24, the transfercarriage 24 in the state where the diameter of the holding ring 24 a isexpanded is moved to the working station F9 where the molding drum 21 isstanding by. And after the diameter of the holding ring is reduced so asto hold the outer circumference of the finished green tire GT, thediameter of the molding drum 21 is reduced so that the green tiretransfer carriage 24 holding the green tire GT is made to leave theworking station F9. After that, the green tire GT is transferred fromthe green tire transfer carriage 24 to the green tire conveyer 25, andthis is conveyed to the tire vulcanization system 3. In the meantime,the second molding carriage 22 is further rotated clockwise on anendless track 23, and the molding drum 21 is moved to the workingstation F1.

The above explanation was made for the tire of the size to which all thetire component members prepared at this tire molding system 2 can beassembled and formed, but for the tire of the size which does not use apart of the tire component members, the corresponding operations aremerely skipped.

Also, the tire component members to be assembled at the molding system 2are not limited to the above but addition/omission is possible asappropriate according to a group of sizes to be handled by the moldingsystem 2. Moreover, the arrangements including the tracks 13 and 23 arenot limited to the above, either, but can be chosen as appropriateaccording to the manufacturing conditions, space restriction, etc. Inthe example shown in FIG. 2, for example, the working stations F1 to F8are provided on both straight portions parallel with each otherconstituting the track 23, but they can be provided only one of thestraight portions, which makes the layout narrow and long in this case.

Moreover, in this tire manufacturing method, among the idle time of eachworking station corresponding to each tact determined based on themolding sequence specified in advance, the tact time can be changed foreach tact so that the shortest idle time becomes shorter, by which thenumber of tires molded per unit time can be increased and theproductivity can be improved.

The size of tires assembled at each working station is changed at eachtact, that is, each moment ticking by tact time, but time required forassembling actual tire component members at each working station can beknown in advance for processes per size, and therefore, the idle timeobtained by subtracting an actual required time from the tact timecorresponding to each tact can be known for each working station, andthe idle time at the working station with the shortest idle time, thatis, the shortest idle time can also be known.

If the tact time is constant regardless of tact, the shortest idle timeis changed according to the size in each tact corresponding to eachworking station determined based on the molding sequence specified inadvance, but since the shortest idle time at each tact can be known asabove, the tact time can be changed in advance so that the shortest idletime becomes shorter or preferably zero, by which the shortest idle timecan be reduced and the productivity can be improved.

In the conventional tire molding system, it was not possible to moldmixture of green tires in different sizes in a predetermined tact timesince a lot of time is required to switch the size of each of the tirecomponent members and complicated molding drum. In the molding system 1of this preferred embodiment, green tires of optional two differentsizes chosen from a group of sizes specified in advance can be moldedcontinuously at a predetermined tact time, the point of which will bedescribed below.

A method for enabling such a tire molding process for mixture ofdifferent sizes is to constitute the tire component members by one typeof member element determined in advance and common to the group of sizesto be molded by this molding system 2 and to mold a green tire byassembling a predetermined amount of the member element for each of thetire component members for all the sizes in the above group.

A first assembling method of the tire component members for the mixedmolding of different sizes employs a rubber ribbon as the above memberelement, in which the rubber ribbon of a predetermined material extrudedcontinuously through a die with a predetermined sectional shape is woundspirally on a cylindrical or a toroidal molding drum, and this islaminated in a predetermined sectional shape so as to assemble this tirecomponent member. For simplification, this method is referred to as“ribbon lamination method” in this specification.

FIG. 9 is a diagram explaining this method, and this ribbon laminationmethod is, as shown schematically in the side view in FIG. 9(a), amethod in which a rubber ribbon R is continuously extruded from anextruder EX having a die with a predetermined section, this ribbon R isheld by a ribbon applying device AP while a body of rotation D isrotated, and the rubber ribbon R is laminated in the spiral state on thecircumference of the body of rotation D while controlling the positionand angle so that a laminated body with a required section is formed. Asin FIGS. 9(b) and (c) showing the laminated body in sectional views,according to this method, since using the rubber ribbon R in the samesectional shape, both a wide and thin laminated body A1 with the widthof W1 and the thickness of t1 and a narrow and thick laminated body A2with the width of W2 and the thickness of t2 can be formed, assemblingof tire component members corresponding to different sizes can beaccomplished without requiring time for switching by programmingbehaviors of the ribbon applying device AP corresponding to each of thesizes in the group in advance and choosing a program to be executedaccording to the size.

A second assembling method of the tire component members for the mixedmolding of different sizes is a method in which a continuous sheet witha predetermined width made of a predetermined material is cut off to apredetermined length for each size, the predetermined number of thecut-off narrow pieces are joined together for each size so that thecut-off faces of the narrow pieces are aligned in the circumferentialdirection on the molding drum. For simplification, this method isreferred to as “predetermined-width narrow-piece method” in thisspecification.

FIG. 10 is a diagram explaining this method referring to a rubber memberwith cord, and in this predetermined-width narrow-piece method,surface-treated cords TC are reeled out of a plurality of reels RL andaligned through an alignment roller AR, they are passed through aninsulation head IH, where they are passed through the rubber extrudedfrom the extruder EX so that the cord TC is covered by rubber to have arubber strip CGS with cord of a predetermined width, and this strip CGSis passed through a pull roller PR and a festoon FT and guided to anapplying head AH. By this applying head AH, this strip CGS is disposedon the body of rotation D in parallel or at an inclined angle withrespect to the axis of the body of rotation D and then, the strip CGS iscut off to the cutting length corresponding to a width W3 of this tirecomponent member on the body of rotation D and next, the body ofrotation D is rotated by an angle corresponding to the circumferentiallength of the dimension obtained by subtracting a joint margin from thewidth of this strip CGS along the body of rotation in thecircumferential direction, and the above operation of the applying headAH is repeated by the number of times determined according to this sizeso that this rubber member with cord is assembled for one cycle of thetire.

According to this method, by setting the dimension of the strip width D3less the joint margin to the common divisor of the circumferentiallength corresponding to all the sizes of the above group to be handledof this tire component member, all of these sizes can be supported onlyby changing the cutting length W3 and the number of pieces to be appliedaccording to the size, by which assembling of tire component memberscorresponding to different sizes can be accomplished without requiringtime for switching by programming movement strokes and the number ofmovement times of the applying head AH corresponding to each of thesizes in the group in advance and choosing a program to be executedaccording to the size.

In this tire molding system 2, among the above mentioned tire componentmembers, the squeegee member SQ, the tread under-cushion member TUC, thebase tread member BASE, the cap tread member CAP, the antenna memberATN, the sidewall member SW and the rubber chafer member GCH can beassembled by the above-mentioned ribbon lamination method. And each ofassembling devices corresponding to these members is provided withextruders 17 a, 30 a, 31 a, 33 a, 32 a, 34 a and 35 a, respectively, inthe order of these members.

Also, the inner liner member IL, the inner- and outer-layer carcassmember P and the inner- and outer-layer belt members 1B and 2B can beassembled by the above predetermined-width narrow-piece method. Inassembling the inner liner member IL, a simple rubber sheet of aconstant width is extruded from an extruder 15 a as a strip used forthis, instead of the rubber strip with cord in FIG. 10, and this is cutoff on the conveyer 15 b to the length corresponding to the tire size tobe handled. The cut-off narrow pieces are joined sequentially on atransfer drum 15 c to form a sheet for a single tire and then, after thetransfer drum is turned pivotally circumscribing the cylindrical moldingdrum 11, these drums 11 and 15 c are rotated in synchronization, andthis sheet is transferred onto the molding drum 11 so as to assemble theinner liner member IL.

In assembling the carcass member P, after a plurality of cords reeledout of a reel stand 18 a are aligned, the rubber is extruded from anextruder 18 b and the cord is covered by rubber, the rubber strip withcord CGS formed at this stage is applied onto a transfer drum 18 c andcut off thereon to a predetermined length according to the tire size tobe handled, and after the predetermined number of cut-off narrow piecesare joined together to prepare a carcass member sheet for a single tire,the transfer drum 18 c is moved to circumscribe the cylindrical moldingdrum 11, and these drums 11 and 18 c are rotated in synchronization soas to transfer this sheet onto the molding drum 11 and to assemble thecarcass member P.

For the tire size of the structure in which two layers of the carcassmember P are assembled, after the carcass members in both layers for asingle tire are aligned and prepared on the transfer drum 18 c in thecircumferential direction, the transfer drum 18 c is brought intocontact with the molding drum 11 corresponding to an assembling timingof each member and separated.

Also, for the inner-layer side belt member 1B, after a plurality ofcords are reeled out of a reel stand 27 a and aligned, the cord iscovered by rubber by extruding the rubber from an extruder 27 b, and therubber strip with cord CGS formed at this stage is directly applied ontothe molding drum 21, but since it is necessary to apply them along thecord in the direction inclined with respect to the tire axis, while themolding drum 21 is rotated, the applying device is moved in the axialdirection of the molding drum 21 in synchronization and the narrowpieces are applied. The outer-layer side belt member 2B is similarlyassembled.

Members other than the above-mentioned members assembled by the ribbonlamination method or the predetermined-width narrow-piece method areassembled as follows. The canvass chafer member CCH is assembled byreeling out a roll of a predetermined width formed in another process,cutting it to the length corresponding to a necessary circumferentiallength and winding it around the molding drum 11, but the axialdirectional position for winding is constituted variably. Also, thewidth of the canvas chafer member CCH is shared by as many sizes aspossible in a range not causing a problem on tire performances.

With regard to the preset beads PB, they are prepared in a bead stock 19b for each size in advance and the preset beads PB in different sizesare taken up by a bead handing robot 19 a according to the requestedsize so that many sizes are supported.

With regard to the spiral layer member SL, a roll of a narrow rubberwith cord is set and this is reeled out and wound on the molding drum 21in the spiral shape so as to assemble this member, but different sizescan be supported by changing the number of winding times at this timeaccording to the size. The tires with different rim size are handled bychanging the toroidal molding drum 21, but the second molding unit 5 isprovided so as to exchange the drums within a predetermined tact time.

Also, the cylindrical drum 11 is constituted capable of supporting tirecomponent members with different widths and diameters, while thetoroidal molding drum 21 is constituted capable of optionally changingan interval between the right and left bead lock parts 21 b and the corebodies 21 a so that tire components members with different widths can behandled.

In other words, in the second molding unit 5, a rail portion of theendless track 23 corresponding to the working station F1 is providedcapable of movement to a drum switching station D1 arranged outside thistrack, and this drum switching station D1 is constituted capable ofturning the moved rail portion pivotally by a predetermined angle. Inorder to switch the size of the molding drum 21, first, at the workingstation F1, the molding carriage 22 on which the molding drum 21 to beejected is fixed to the rail, and then, the rail portion with thismolding carriage 22 mounted is moved to the drum switching station D1,this is turned pivotally, and a rail at an empty carriage storage X1 isconnected to the moved rail portion so as to eject the molding drum 21together with the molding carriage 22 to the carriage storage X1. Andafter that, the drum switching station D1 is further turned, the movedrail portion is connected to a rail of a carriage storage X2, and themolding carriage 22 with the molding drum 21 for a new size which hasstood by at the carriage storage X2 is moved into the drum switchingstation D1. Then, after this is turned pivotally, it is returnedtogether with the rail portion to the working station F1 so that themolding drum 21 can be switched in a short time.

Next, the tire vulcanization system 3 constituting the tiremanufacturing system 1 will be described. FIG. 11 is a schematic planview showing the tire vulcanization system 3 in which two similarvulcanization systems 100 are arranged adjacent to each other. In thefollowing explanation, an “uncured tire” or a “tire which has not beencured yet” is synonymous with a green tire.

In each of the vulcanization systems 100, a single die opening/closingstation 112 is arranged, and with the die opening/closing station 112 atthe center, four vulcanization stations 111 are arranged on an arc R2 onone side of a straight line L connecting the centers of each of the dieopening/closing stations 112 of the two vulcanization systems 100. And adie relay station 181 is provided at a position almost equidistant fromeach of at least two vulcanization stations 111 on the outside portionof the arc R2, and a die inserting/ejecting device 182 preferably in theturntable structure is provided so as to take out used vulcanizationdies from each of the vulcanization stations 111 in the vicinity of thisdie relay station 181 and to insert a vulcanization die to be used next.

Also, at each of the vulcanization systems 100, four units of mobilevulcanization units 113 reciprocating between each of the fourvulcanization stations 111 and the die opening/closing station 112 isprovided. FIG. 11 shows a state where, among these four mobilevulcanization units 113, only the mobile vulcanization unit 113corresponding to the rightmost vulcanization station 111 of the leftvulcanization system 100 is displaced to the side of the dieopening/closing station.

With respect to the straight line L connecting the centers of the dieopening/closing stations 112, a tire transfer device 114 for the dieopening/closing station for taking out a cured tire from the dieopening/closing station 112 or for inserting an uncured tire into thedie opening/closing station 112 is provided on the side opposite to theregion where the vulcanization station 111 is arranged. At the dieopening/closing station 112, a tire is housed in the die with theposture with its central axis perpendicular, and this tire transferdevice 114 inserts/takes out the tire in this posture with respect tothe die opening/closing station 112.

Also, within the operation range of this tire transfer device 114, abladder attaching/detaching station 108 provided with a bladderattaching/detaching device 108 a for attaching a bladder B to theuncured tire GT and detaching the bladder B from the cured tire T and aloading/unloading station 118 are provided, and at the loading/unloadingstation 118, an uncured tire stand 116 for temporarily storing theuncured tire GT before the bladder B is attached and delivering it tothe tire transfer device 114 and a cured tire stand 117 for receivingthe cured tire T from which the bladder has been removed from the tiretransfer device 114 and temporarily storing it are arranged side byside. And between these stations 108 and 118, at least one but two unitsin FIG. of manipulators 175 and 176 for delivering the tire GT and T toeach of the stations 108 and 118 are disposed.

The stands 116 and 117 arranged adjacent right and left on the sameplane in this FIG. can be arranged adjacent vertically or fore and aft,and in either case, it is preferable that carrying-in of the uncuredtire GT onto the stand 116 and carrying-out of the cured tire T from thestand 117 are performed using a conveying means such as a belt conveyer,not shown.

And also, it is preferable that, in addition to the above, a post-curestation 115 is provided within the operation range of the tire transferdevice 114, and at this station 115, a post-cure inflator 115 a isdisposed for conducting PCI processing on the cured tire T including thebladder. The post-cure inflator 115 a is constituted so that each tireis supported at four points to enable PCI processing for four tires atthe same time and the tires are supported in the posture with theircenter axes horizontal. Also, at the bladder attaching/detaching station108 and the uncured tire stand 116 as well as the cured tire stand 117,tires are fixed in the posture with their center axes vertical.

Each of the vulcanization stations 111, the die opening/closing station112 and the mobile vulcanization unit 113 reciprocating between themconstituting this vulcanization system 100 will be described. FIG. 12 isa side view showing the mobile vulcanization unit 113. This mobilevulcanization unit 113 is provided with a vulcanization mold 130 forstoring the tire T and a bladder B for specifying the inner face shapeof the tire T in a cavity.

The vulcanization mold 130 is provided with an upper mold 131, a lowermold 132 and a container 133, forming in combination the cavity forstoring the tire T, and capable of separating them from each other inthe vertical direction for loading/unloading the tire. And the lowermold 132 is provided with a lower side mold 136 corresponding to one ofside portions of the tire, and the upper mold 131 is provided with anupper side mold 135 corresponding to the other side portion of the tireand a plurality of segment molds 134 combined in the circumferentialdirection in the annular shape, forming an outer-face shape of the tiretread portion and movable in the radial direction.

And the mobile vulcanization unit 113 has an upper platen 161 and alower platen 162 which are brought into contact with both end faces ofsuch vulcanization mold 130 to constitute a heating platen part, and aheat medium supply hose 167 is connected to each of the platens 161 and162. According to this, through the hose 167, these platens 161 and 162can be heated by supplying the heat medium, which is steam, for example,to a heat-medium jacket provided inside these platens 161 and 162, andthis heat is transmitted to the vulcanization mold 130 to be broughtinto contact so as to cure the tire.

Moreover, the mobile vulcanization unit 113 is provided with an upperend plate 163 and a lower end plate 164 for integrally holding thevulcanization mold 130 and each of the platens 161 and 162 brought intocontact with the both end faces between them, and has a plurality of tierods 165 for connecting these end plates 163 and 164 to each other and ahydraulic jack 169 mounted on the lower end plate 164 for pressing thevulcanization mold 130 onto the upper end plate 163 to fasten thevulcanization mold 130. These end plates 163, 164, the tie rods 165 andthe hydraulic jack 169 constitute a mold lock means for integrallyfastening the vulcanization mold 130 and the upper and lower platens 161and 162 in cooperation.

Also, the lower tip end of the tie rod 165 is fixed to the lower endplate 164 and the upper tip end of the tie rod 165 is engaged with theupper end plate 163 through the tie plate 166, and this tie plate 166 isconstituted so that the tie rod 165 can be engaged with the upper endplate 163 or the engagement can be cancelled by rotating and displacingthis tie plate 166 around the center of axis of the vulcanization mold.

Here, the upper mold 131, the upper platen 161, the upper end plate 163and the tie plate 166 constitute an elevation unit part 172 which ismoved integrally with the upper end plate 163 when it is hoisted up.

Next, the vulcanization station 111 and the mold opening/closing station112 will be described. FIG. 13 is a front view showing one of the moldopening/closing station 112 of the vulcanization system 100 in FIG. 11and the vulcanization stations 111 provided opposite to it, and FIG. 14is a plan view showing an arrow view of XIV-XIV in FIG. 13, but as forthe vulcanization stations 111, all the four units arranged around themold opening/closing station 112 are shown.

Each of the vulcanization stations 111 has a heat-medium supply port 156for supplying the heat medium and is provided with a vulcanization unitreciprocatory driving device 140 for reciprocating and displacing themobile vulcanization unit 113 between this vulcanization station 111 andthe mold opening/closing station 112.

This vulcanization unit reciprocatory driving device 140 is comprised ofa vulcanization unit driving part 151 and a vulcanization unitsupporting guide part 141, and the vulcanization unit driving part 151is provided with a driving bar 155 fixed to one link of a link chain 154extended between two sprockets 152 and driven by a motor 153. The tipend of the driving bar 155 can be detachably connected by a connectingmeans, not shown, to the end part of the mobile vulcanization unit 113,that is, a portion located opposite to the mold opening/closing station112, and by driving the motor 153 to reciprocate and displace the linkchain 154, the mobile vulcanization unit 113 can be reciprocated anddisplaced.

The vulcanization unit supporting guide part 141 is provided with aplurality of rollers 142 and a roller mounts 143 for supporting them,and these rollers 142 are arranged in two rows between the correspondingvulcanization station 111 and the mold opening/closing station 112 inparallel with the straight light connecting them to each other. In themeantime, on the lower face of the mobile vulcanization unit 113, twoguide rails 171 are mounted in parallel with this traveling direction,and by moving this guide rail 171 on the corresponding row of therollers 142 along this row, the mobile vulcanization unit 113 can bereciprocated and displaced with respect to the mold opening/closingstation 112.

As mentioned above, by constituting the vulcanization unit supportingguide part 141 of the vulcanization unit reciprocatory driving device140 by the rollers 142 with short shafts laid on the movement section ofthe mobile vulcanization unit 113, as shown in FIG. 11, the extremelysimple and low-cost tire vulcanization system 100 can be realized.

Moreover, as shown in FIG. 11, even at the mold opening/closing station112 where the vulcanization unit reciprocatory driving device 140provided on each of the vulcanization stations 111 crosses each otherand its vicinity, the vulcanization unit supporting guide parts 141 orthe vulcanization unit supporting guide part 141 and other mobilevulcanization units 113 do not interfere with each other when they areprovided.

Also, in movement of the mobile vulcanization unit 113, since thevulcanization unit 113 can be moved with the heat-medium supply hose 167for supplying the heat medium from the heat-medium supply port 156connected to the upper and lower platens 161 and 162 of the mobilevulcanization unit 113, vulcanization can be continued even duringmovement of the mobile vulcanization unit 113, and by making use of thismovement time as a part of the vulcanization time to the maximum, thecycle time can be reduced for that time, and moreover, equipment costscan be lowered and a risk of leakage of the heat medium from theconnection part can be reduced.

The mold opening/closing station 112 is provided with a moldopening/closing device 121 at its center, as shown in FIG. 13, forelevating the elevation unit part 172 of the mobile vulcanization unit113 which has been moved. This mold opening/closing device 121 isprovided with a base 122 fixed through a column built from a floor faceFL and a vertical unit 124 guided by a guide 123 mounted to this base122 and elevated by a driving device, not shown. This vertical unit 124is provided with an elevation unit part lock holding mechanism 125 forconnecting or separating the upper end plate 163 and the tie rod 165 byrotating the above tie plate 166 of the mobile vulcanization unit 113and for holding or releasing the holding of the upper end plate 163.

In this tire vulcanization system 3, after the uncured tire GT isreceived from the molding system 2 and cured in synchronization with themolding system 2, the cured tire T is ejected to an inspection system 6for conducting inspection of the tire in synchronization with thesesystems 2 and 3. A series of operations from reception of the uncuredtire GT to ejection of the cured tire T will be explained referring tothe above FIG. 11.

The uncured tire GT conveyed from the previous process is loaded ontothe uncured tire stand 116. After this uncured tire GT is transferred tothe bladder attaching/detaching station 108 by the manipulator 175, thebladder B is attached inside the uncured tire GT at the bladderattaching/detaching station 108, and then, by the tire transfer device114, the uncured tire GT with the bladder B attached is transferred tothe mold opening/closing station 112. Since the mobile vulcanizationunit 113 after the cured tire T had been removed has been standing by atthe mold opening/closing station 112 with its vulcanization mold 130open at this time, the uncured tire GT is set onto this vulcanizationmold 130.

After the tire transfer device 114 is retreated from the moldopening/closing station, the mold opening/closing device 121 is lowered,the elevation unit part 172 of the mobile vulcanization unit 113 islowered, and the elevation unit part lock holding mechanism 125 and thehydraulic jack 169 are operated so as to lock the elevation unit part172 with the other portions of the mobile vulcanization unit 113.

After that, this mobile vulcanization unit 113 is moved to thevulcanization station 111 by the vulcanization unit reciprocatorydriving device 140 so as to vulcanize the uncured tire GT stored in thisat the vulcanization station 111. When the vulcanization is completed,the mobile vulcanization unit 113 is moved to the mold opening/closingstation 112 by the vulcanization unit reciprocatory driving device 140,and the vulcanization mold 130 is released by the mold opening/closingdevice 121 of the mold opening/closing station 112 so that the curedtire T can be taken out thereof.

After that, this cured tire T is transferred to the post-cure station115 from the mold opening/closing station 112 using the tire transferdevice 114, and PCI processing is applied to this tire at the post-curestation 115. After the PCI processing is completed, the cured tire T isremoved by the tire transfer device 114 again from the post-cure station115 and transferred to the bladder attaching/detaching station 108.

At the bladder attaching/detaching station 108, the bladder is removedfrom the cured tire T to which the bladder has been attached, and thistire T is loaded on the cured tire stand 117 using the manipulator 176and then, conveyed to the next process.

In the above-mentioned vulcanization system 3, a function to vulcanizetires, a function to open/close the vulcanization mold 130, and afunction to attach/detach the bladder to/from the tire are provided indistribution to each of separate stations so as to improve operationrates of each function, but the vulcanization system 3 can beconstituted by those having these functions altogether at thevulcanization station. Also, in this preferred embodiment, thevulcanization station is arranged on the arc with the moldopening/closing station at the center, but another arrangement such asvulcanization stations in the linear state, for example is allowed.

FIG. 15 is an arrangement plan showing a tire manufacturing system 1A ofanother preferred embodiment, and in this manufacturing system 1A, avulcanization system 3A is different from the above-mentioned preferredembodiment. This vulcanization system 3A is provided with a plurality ofvulcanization machines 91 linearly aligned in two rows and awater-cooling PCI 92 arranged corresponding to each of the vulcanizationmachines. And in vulcanizing tires with this system 3A, first, a greentire received form the molding system 2 is inputted to each of thevulcanization machines 91, where the green tire is attached to abladder, and the vulcanization mold attached to the vulcanizationmachine 91 is closed to start vulcanization. After the vulcanization iscompleted, the mold is released for each of the vulcanization machinesto take out the cured tire from the bladder and this is attached to thePCI 92 and then, they are conveyed to the inspection system by anejection conveyer 93.

Moreover, the arrangement of the molding system, the vulcanizationsystem and the inspection system in the tire manufacturing systemaccording to the present invention can be made in many other ways inaddition to the above, and the arrangement of the working stations andthe vulcanization station in each of systems can be various. FIGS.16(a), 16(b), 17(a), 17(b), 18(a) and 18(b) show those arrangementexamples. In these FIGS. , the working station for molding is indicatedby a rectangle, a vulcanization station by a circle and the flowdirection of the tire in the middle of manufacturing by an arrow. Also,the reference numerals of each system are common to all the arrangementexamples, in which the molding system is 2, the vulcanization system is3, the inspection system is 6, the first molding unit of the moldingsystem is 4, and the second molding unit is 5. The arrangement shown inFIG. 16(b) corresponds to that shown in this preferred embodiment, andthe vulcanization system shown in FIGS. 18(a) and (b) is constituted sothat the vulcanization station itself is moved on the arc.

INDUSTRIAL APPLICABILITY

As obvious from the above, according to the present invention, since thecarcass band is rolled up around the bead core by the toroidal moldingdrum capable of expansion/contraction in the toroidal shape, a tire inthe conventional structure with high reliability can be formed. Andsince the green tire is removed from the toroidal molding drum at theend of the molding process, it is only necessary to heat the green tirein the next vulcanization process, whereby energy is not wastefullyconsumed. Also, since the green tire is molded based on the moldingsequence predetermined in advance, including combination of green tireswith different sizes in tandem chosen from the above group of sizesaccording to the need, tires with mixed plural sizes can be moldedcontinuously.

1. A tire manufacturing method having a process for, in manufacturingproduct tires in plural sizes chosen from a group of sizes specified inadvance, moving a tire being molded sequentially between stations of amolding system having a plurality of working stations, sequentiallyassembling tire component members specified in advance corresponding toeach working station and molding a green tire at a predetermined tacttime, and a process for vulcanizing the molded green tire, to beperformed at one or more working stations of said molding system:molding a green tire based on the molding sequence specified in advance,including combination of green tires in different sizes in tandem chosenas necessary from said group of sizes, disposing a carcass band and bothbead cores on a toroidal molding drum whose diameter can beexpanded/reduced in the toroidal shape and locking the bead cores,expanding the diameter of the molding drum, toroidally extending thecarcass band between both bead cores, rolling up the side portion of thecarcass band around the bead cores outward in the radial direction,assembling tire component members with the bead cores locked to thetoroidal molding drum and molding the green tire, reducing the diameterof the molding drum, unlocking the bead cores, and removing the greentire from the molding drum.
 2. A tire manufacturing method according toclaim 1, wherein, in forming said carcass band, this member is assembledonto a cylindrical molding drum to form a carcass band at workingstations corresponding to an inner liner member and a carcass member,respectively, and then, the carcass band is removed from the cylindricalmolding drum, in molding said green tire, after said process for rollingup the side portion of the carcass member on the toroidal molding drum,a belt member, a tread member and a sidewall member are assembled at therespective corresponding working stations.
 3. A tire manufacturingmethod according to claim 1, wherein at least one tire component memberto be assembled at said working station is comprised of one type ofmember element specified in advance and common to said group of sizes,and a green tire is molded by assembling the member element by an amountspecified in advance for each tire component member for all the sizes insaid group.
 4. A tire manufacturing method according to claim 3, whereinat least one of said tire component members has a rubber ribbon made ofa predetermined material continuously extruded through a die with apredetermined sectional shape as said member element, this rubber ribbonis wound on a cylindrical or a toroidal molding drum in the spiral shapeand this is laminated in the predetermined sectional shape, and thistire component member is assembled.
 5. A tire manufacturing methodaccording to claim 3, wherein at least one of said tire componentmembers has a continuous sheet with a predetermined width made of apredetermined material as said member element, this continuous sheet iscut into the length specified in advance per size, narrow pieces in thenumber predetermined for each size are joined to each other so that thecut-off faces of the cut-off narrow pieces are aligned in thecircumferential direction on the molding drum, and this tire componentmember is assembled.
 6. A tire manufacturing method according to claim3, wherein a tread member and a sidewall member are included in tirecomponent members having a rubber ribbon made of a predeterminedmaterial continuously extruded through a die with a predeterminedsectional shape as said member element, this rubber ribbon is wound on acylindrical or a toroidal molding drum in the spiral shape and this islaminated in the predetermined sectional shape as said member element,and an inner liner member, a carcass member and a belt member areincluded in tire component members having a continuous sheet with apredetermined width made of a predetermined material as said memberelement, this continuous sheet is cut into the length specified inadvance per size, narrow pieces in the number predetermined for eachsize are joined to each other so that the cut-off faces of the cut-offnarrow pieces are aligned in the circumferential direction on themolding drum as said member element.
 7. A tire manufacturing methodaccording to claim 3, wherein, as for at least one tire componentmember, said member element is directly assembled onto a cylindrical ora toroidal molding drum.
 8. A tire manufacturing method according toclaim 3, wherein, as for at least one tire component member, said memberelement for a single tire is combined and then, the combined memberelement is assembled on a cylindrical or a toroidal molding drum.
 9. Atire manufacturing method according to claim 1, wherein among idle timeat each of the working stations corresponding to each tact determinedbased on said molding sequence specified in advance, a tact time ischanged for the respective tact so that the shortest idle time becomesshorter.
 10. A tire manufacturing method according to claim 1, whereinan estimate equation is prepared in advance to estimate a primaryharmonic component of radial run-out in a green tire caused by arelative displacement or angular displacement between the center of axisof the carcass band and the center of axis of the bead core in settingthe bead core on the outer circumference of the carcass band, radialrun-out of the green tire is measured for one cycle and an invertedwaveform in which the primary harmonic component is inverted isobtained, in molding a tire of the same size in said molding systemthereafter, a relative displacement or an angular displacement betweenthe center of axis of the carcass member and the center of axis of thebead core causing this inverted waveform is obtained by back calculationof said estimate equation, and the position or the angle of at leasteither one of the bead core axis centers is changed by the magnitude ofthe displacement acquired from this estimate equation in the directionof the displacement acquired from this estimate equation so as to setthe bead core on the carcass band.
 11. A tire manufacturing methodaccording to claim 1, wherein vulcanization of the molded green tires isstarted sequentially at said predetermined tact time and vulcanizationof these tires is finished at said predetermined tact time.
 12. A tiremanufacturing method according to claim 1, wherein inspection of thevulcanized tire is started at said predetermined tact time.